/*
 * Copyright Terracotta, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.ehcache.clustered.server.store;

import org.ehcache.clustered.common.internal.messages.EhcacheEntityMessage;
import org.terracotta.entity.ConcurrencyStrategy;

import java.util.function.ToIntFunction;

/**
 * MessageToTrackerSegmentFunction
 */
class MessageToTrackerSegmentFunction implements ToIntFunction<EhcacheEntityMessage> {

  private final ConcurrencyStrategy<EhcacheEntityMessage> concurrencyStrategy;

  MessageToTrackerSegmentFunction(ConcurrencyStrategy<EhcacheEntityMessage> concurrencyStrategy) {
    this.concurrencyStrategy = concurrencyStrategy;
  }

  @Override
  public int applyAsInt(EhcacheEntityMessage value) {
    // Concurrency is 1 based, segments are 0 based
    return concurrencyStrategy.concurrencyKey(value) - 1;
  }
}
